PMID: 14680831

Authors:

de Azevedo WF Jr, Canduri F, dos Santos DM, Pereira JH, Bertacine Dias MV, Silva RG, Mendes MA, Basso LA, Palma MS, Santos DS

Title:

Crystal structure of human PNP complexed with guanine.

Journal:

Biochem Biophys Res Commun. 2003 Dec 19;312(3):767-72.

Abstract:

Purine nucleoside phosphorylase (PNP) catalyzes the phosphorolysis of the N-ribosidic bonds of purine nucleosides and deoxynucleosides. PNP is a target for inhibitor development aiming at T-cell immune response modulation and has been submitted to extensive structure-based drug design. More recently, the 3-D structure of human PNP has been refined to 2.3A resolution, which allowed a redefinition of the residues involved in the substrate-binding sites and provided a more reliable model for structure-based design of inhibitors. This work reports crystallographic study of the complex of Human PNP:guanine (HsPNP:Gua) solved at 2.7A resolution using synchrotron radiation. Analysis of the structural differences among the HsPNP:Gua complex, PNP apoenzyme, and HsPNP:immucillin-H provides explanation for inhibitor binding, refines the purine-binding site, and can be used for future inhibitor design.